US2681295A - Process for flameproofing textiles with polyphosphonitrilic ester - Google Patents

Description

Patented June 15, 1954 PROCESS 'FOR FLAMEE WITH POLYPHOSPH wCarl Hamalainen,

. by. .the Secretary N oDrawing. Application ROOFING TEXTILES ONITRILIC ESTER New Orleans, La., assignor to the United States of America of Agriculture as represented December 5, 1952,

- Serial No. 324,427

. 3 Claims.

(Grantcd umler Title 35, U. S. Code (1-952),

A non-exclusive, irrevocable, royalty free license in the inventionherein described, for all governmental purposes, throughoutthe world, with the power to grant sub'licenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to .thefiameprooflng of textiles such as threads'and fabrics. i More particularly, the invention provides a. process of coating the fibers of a textile with a fiarneprooiing agent which will remain on the fibers throughout numerous launderings.

In general; the process of the present invention comprises, reacting mixed polyphosphonitrilic chlorides with .a chloro or bromo polyhalopropyl alcohol in the presence of pyridine, impregnating a textile with the mixed esters so produced, and curing the wet textile.

Suitable polyphosphonitrilic chlorides include thehigh polymers of polyphosphonitrilic chloride and mixtures. of the trimers and tetramers with the higher polymersh .The mixed polyphosphonitrilic chlorides can suitably be'employed in the form of a solute dissolved in the solvent in which they were prepared, solvents such as tetrachloroethane being particularly suitable.

The reaction between the polyphosphonitrilic chlorides and the alcohol is preferably conducted under anhydrous conditions at a temperature of about from to 30 C. in the presence of surficient pyridine to neutralize the hydrochloric acid formed.

Suitable polyhalopropyl alcohols include polyhalo propanols containing at. least two halogen atoms of the group consisting of bromine and chlorine. The 2,3-dihalo alcohols are preferred, especially 2,3-dibromopropanol.

Textiles can suitably be flameproofed by impregnating them with the esters dissolved in a The use of acetone solutions of the esters containing from about 5 to 15% nonvolatile materials is preferred. The esters can suitably be isolated from the reaction mixture by conventional methods such as pouring the reaction mixture into a selective solvent miscible temperature of the sec. 266) The textiles wet with thesolution of th esters can suitably be cured I by conventional textile curing procedures at temperatures ranging from about room temperature to the decomposition textile for times ranging from a few minutes to several days, using the lower temperatures with the longer times. Where the tensile strength of the flameproof: textile is important, the use of the lower temperatures is preferred.

. proofing imparted to the. varioustextile. fabrics was measured by cutting the-treated fabrics into strips approximately onei'cm. in width, fastening the strip so that the strip about 45 .135. or180"-from the fastener, and igniting the far end. With no flameprooflng agent, the fabrics used in the examples failed to pass the 0 flameproofing test, 1. e., the flame would propagate itself down a vertical strip of the fabric lighted at the top. A complete flameproof fabric will pass the 180 test, 1. e., a vertical strip of the fabric will not support combustion when lighted at the bottom.

Example 1 A solution of about 1 part of mixed polyphosphonitrilic chlorides dissolved in 10 parts of pyridine was mixed with about 5 parts of 2,3-dibromopropyl alcohol and allowed to react at room temperature (approximately 27 C'.) for about 24 hours.

A piece of 80 sq. cotton cloth was impregnated with the reaction mixture (to a wet pickup of approximately l00%) and heated for 30 minutes at C. The so-treated cloth passed the 180 flame test but was somewhat tendered.

A piece of similar cloth, similarly impregnated with the same reaction mixture, then dried 4 hours at room temperature, passed the 180 flame test and was not tendered. This latter sample passed the 180 flame test after 30 minutes boiling in 0.5% alkaline soap solution. After boiling in 2 sodium hydroxide solution for six hours this sample still passed the flame test.

Example 2 Five parts of a 20% solution of mixed polyphosphonitrilic chlorides in tetrachloroethane was mixed with 5 parts of pyridine and 4.5 parts of 2,3-dibromopropyl alcohol and allowed to react for about 24 hours at room temperature. The reaction mixture was poured into about 40 parts ethyl alcohol. About 2.6 parts of a rubbery ester precipitated and were isolated.

4 minutes at 110 C. After washing and drying, the sample had increased in weight by about 17%. The samples passed the 135 flame test.

I claim:

Samples of 80 sq. cotton cloth were padded 5 1. A process comprising, reacting mixed polywith 5%, and solutions of the above phosphonitrilic chlorides with a polyhaloproester in acetone. One set of samples, series A, panolcontaining at least two atoms of the group was allowed to air-dry overnight. The second consisting of bromine and chlorine in the presset, series B, was cured in an oven for minutes ence of pyridine, impregnating a textile with at 110 C. All of the samples were washed 15 min- 10 the esters so produced, and curing the wet textile. utes in running hot tap water and then dried 2. The process of claim 1 in which the polyin the oven 30 minutes at 110 C. All of the halopropanol is 2,3-dibr0mopropy1 alcohol, and samples were subjected to 30 minutes boil in the textile is a cotton fabric.

0.5% alkaline soap solution and to 6 hours re- 3. A process of fiameproofing cotton textiles fluxing in aqueous 2% NaOI-I. Each of the latter 15 mp isin impr a i the t xtil s with th treatments was followed by 15 minutes hot tap esters produced by reacting a polyhalopropanol water washing and oven drying for 30 minutes containing at least two atoms of the group conat 110 C. The following table summarizes the sisting of bromine and chlorine witha mixture flame tests and analyses of the sotreated of polyphosphonitrilic chlorides in the presence samples. 20 of pyridine.

Initial Wt. In- Flame Tests Samp. Nbr. 'gg gg gg Cure 313158;? A M 2 percent peigiant After Wash Launfi ry N]? 5%inacetone.-. Air dry-overnight 7.8 4.6 (.54% P). 45% 45 .3e% P). 113.. o OvendIy-30 min. 0... 7.2 7.0 (.77%P) 90 90 .54 2A.. l0%inacet0ne Air dryovernight 13.9 10.2 135 (1.08%).-. 90 90 (.64%) 213.. o Oven dry-30 min. 110C... 13.6 12.6 (1.25%)... 180 5(.98%) 3A 15%inaceto 0.. Air dry-overnight 20.0 16.2 180 1.59% 180 5 1.04% 313 .do Oven dry30 min. 110 o... 10.3 17.0 180 (1.58%)... 180 135 1.27%

Example 3 References Cited in the file of this patent A solution of about 1 part of mixed polyphos- UNITED STATES PATENTS, phonitrilic chlorides dissolved in about 10 parts pyridine was reacted with about 5 parts 1,3-di- 35 Number Name Date chloropropyl alcohol at room temperature for 36-19365 M 1dg 1ey 1934 period of about 24 hours .1 1 Llpkln 194-0 A piece of 80 sq. cloth was impregnated with 2,427,997 White Sept 1947 the reaction mixture (to a wet pickup of approxi- 2,574,515 Walter e11 911 V- 1951 mately 100%) and heated in the oven for 30 40 2,574,516 Walter et a1. Nov. 13, 1951

Claims (1)

1. A PROCESS COMPRISING, REACTING MIXED POLYPHOSPHONITRILIC CHLORIDES WITH A POLYHALOPROPANOL CONTAINING AT LEAST TWO ATOMS OF THE GROUP CONSISTING OF BROMINE AND CHLORIDE IN THE PRESENCE OF PYRIDINE, IMPREGNATING A TEXTILE WITH THE ESTERS SO PRODUCED, AND CURING THE WET TEXTILE.